@charset "UTF-8";
body {
            background-image: url("img/星空.jpg");
            background-repeat: no-repeat;
            background-size: 100% 100%;
            background-attachment: fixed;      /*图片铺满整个页面*/
        }
        .main {
            width: 500px;
            height: 300px;
            box-shadow: 0 5px 20px 0 #e8e8e8;
            background-color: white;
            border-radius: 10px;
            position: absolute;
            top: 0;
            right: 0;
            bottom: 0;
            left: 0;
            margin: auto;
        }
        .main h2 {
            color: lightseagreen;
            margin-left: 150px;
        }
        .form {
            margin-top: 30px;
            margin-left: 60px;
        }
        .form input {
            width: 300px;
            height: 25px;
            border: 1px solid lightgray;
            outline: none;      /*输入内容时不显示边框*/
        }